print('hello world')
# height = float(input('请输入你的身高(m):'))
# weight = float(input('请输入你的体重（kg)'))
#
# bim = weight / (height**2)
# print("BMI:"+str(bim))
#
# if bim<18.5:
#     print('体重过轻')
# elif bim>=18.5 and bim<24.9:
#     print('正常范围，请注意保持')
# elif bim>=24.9 and bim<=29.9:
#     print('体重较轻')
# else:
#     print('肥胖')
# a = '哈哈哈哈'
# b = 'j j '
# print(a + b)
# a = None
# print(bool(None))
# print(''== None)
# print(0 == None)
# print(0 =='')
a = 7
